I think most professionals in this industry cringe a little when they hear people talk about clouds, and rightly so. It's a sales pitch more than anything, the concept behind it is as old as mainframes and terminals. We're in a constant struggle to keep producing IT services that the companies want yet aren't really willing to pay for and the companies are constantly struggling to get things done cheaper, increase profit margins. I consider it a part of our job to explain how there's different kinds of storage, because believe me, I get the exact same questions like your Mediamarkt example every other day, and I also consider it our job to explain the technical and real pros and cons with cloud computing and virtualization. One thing I'm sure many businesses will realize is that having well defined SLA's will be key when buying cloud services. When they no longer can go next door to yell on the IT guys until they fix the problem and profits starts to disappear during an outage with no apparent person to point fingers at, they will understand the consequences of their budget cuts. I haven't heard of any real cloud service yet that hasn't had major issues and they won't magically disappear in a cloud, just have larger consequences.

I think "Durable storage or Cloud Storage", if there is one should deliver the following:
1. Store Anywhere - with storage replication (write one copy, replicate to many) - in case of data center disaster
2. Application Performance - Application make use of the cloud storage should deliver optimal price versus performance
3. Governance & Compliance - Perhaps policy or procedure need to be revise or re-write to make it relevant

The general statement for Cloud Storage from an article "Cloud Storage For IT":

"Cloud storage is a broad term that typically defines a storage system as highly scalable, can be deployed for internal or external use and typically uses some form of clustered or grid based storage. It may or may not have a host of other features like geographic dispersion, retention capabilities and hardware independence.

When IT looks to cloud storage they are looking to solve the problems of meeting performance demands, dealing with massive data growth, overworked IT staffs and escalating storage costs. Each of these challenges will have a different weighting within the organization and that organization is going to select an architecture that best addresses them. The weighting of the importance of the above challenges will vary between organizations. If it is secondary data, then cost and scalability may be a bigger issue than performance. If it is primary data then performance may be the top priority. "